Going to the Chinese mainland can be dangerous. First-time visitors are often surprised at their freedom, and seasoned travelers may feel comfortable, but foreigners in China do get detained by police for many reasons. When commercial dealings sour business people of Chinese descent, including those from Taiwan and Hong Kong, are especially at risk.

To be sure, China has enacted laws to better protect the rights of criminal suspects. On January 1, a newly-amended criminal procedure law will go into effect with many provisions aimed at remedying some of China’s chronic police abuses. Yet, despite reformers' best efforts, the law has many ambiguities and exceptions. Moreover, rather than fill in the gaps in good faith, in practice China's law enforcement officials frequently twist even clear legal language to their convenience, and sometimes act totally outside or contrary to the law. The system provides no effective way to challenge such government lawlessness, and torture continues to embarrass China's international and domestic commitments to eliminate it.

Every detained foreigner confronts the same problems as detained Chinese citizens. When will someone tell my family or colleagues where I am and why? Can I meet them? Can I meet a lawyer? Who can help me regain my freedom? Most nations rely on international agreements to protect their citizens from arbitrary detention abroad. The Vienna Convention on Consular Relations, to which China adheres, requires detaining governments not only to inform the detained person of his right to have his consulate notified, but also to allow consular officers to visit and arrange legal representation. Many nations have bilateral consular agreements with China that specify more detailed protections for their nationals.

Although these international guaranties are imperfect, they give foreign nationals greater security than that enjoyed by Taiwan people in the mainland. The Republic of China government’s acceptance of the Vienna Convention is no longer recognized, and it has neither a consular agreement nor even formal diplomatic contacts with the People's Republic. Yet millions of Taiwanese visit the mainland, and hundreds of thousands live and work there.

In 2009, Taiwan sought to resolve problems of detained citizens with the Agreement on Joint Cross-Strait Crime-Fighting and Mutual Judicial Assistance concluded by semi-official organizations from both sides. Yet that document merely required each party to "promptly" inform the other of any relevant detention. No specific time limit was stipulated, and the authorities were given discretion to postpone notification if it would "hinder ongoing investigation, prosecution or trial procedures." Moreover, Beijing's subsequent disappointing implementation of this safeguard did little to ease the anxieties of Taiwan visitors, especially business people.

Many in Taiwan anticipated that the long-awaited Cross-Strait Bilateral Investment Protection and Promotion Agreement, which was signed August 9th and reflected considerable progress in establishing methods of resolving cross-strait commercial disputes, would finally guarantee notification of detention in every case, at least for Taiwan investors and their families. They hoped the Agreement would not only require immediate family notification, but also prescribe what information must be given, and the rights of the detainee, his family and their lawyers. To their surprise, neither the Agreement nor its Appendix includes such provisions. Instead, the parties issued a separate "Statement of Common Understanding" that gives the appearance of increased security without the substance.

This unusual Statement provides that, after taking criminal justice "compulsory measures" against Taiwanese investors, their Taiwanese employees or accompanying family members, mainland public security authorities - mention of China's notorious "national security" agency is conspicuously absent - must inform a detained person's family in the mainland within 24 hours. If the detainee's family is not in the mainland, the Statement merely indicates that the police "may" inform the investor's company.

Critics correctly point out that the Statement actually promises nothing more than what is already provided in China’s forthcoming criminal procedure law. At best, the Statement is a vaguely-worded reminder that China’s police should follow their law when dealing with Taiwanese investors, giving notification of the detainee's confinement, his location and the charges against him to the extent required.

The Statement does not make clear that the forthcoming criminal procedure law's notification rule, although an improvement over existing law, contains important exceptions. In cases of allegedly endangering national security or suspected terrorist activities, the rule frees police from the obligation to inform the family if, in their judgment, notification may hinder their investigation. In negotiating the Investment Agreement, Taiwan tried to eliminate applicability of the exceptions, but China asserted that they will still apply even though the Statement is silent about exceptions. In an effort to downplay the significance of these exceptions, a mainland negotiator blithely expressed confidence that Taiwan investors would not become involved in such crimes, but both sides are well aware of occasions when China has charged Taiwan business people with spying that endangered national security.

Some Taiwanese advocates also call for guaranteeing notification to a detained person’s family in Taiwan and improving mechanisms for promptly doing so. Because Taiwan is outside China’s control, direct family notification is not plausible, and, under the 2009 Judicial Assistance Agreement, notification must proceed from mainland authorities to Taiwan authorities to the Taiwan family. But China’s notification has sometimes been slow in practice or even withheld. A specific deadline is essential. Taiwan’s representatives should also be allowed to meet detainees and arrange immediate access to a lawyer. Family visits should also be permitted.

Without further Chinese criminal justice reforms such as those in Taiwan, however, many of Taiwan's suggestions are not likely to be accepted. Unlike in Taiwan, family visits to detained suspects are not generally permitted in China. Detainees' access to lawyers is also restricted in practice or prohibited in certain cases, and Chinese lawyers, unlike their Taiwan counterparts, do not have the right to be present during interrogations. These major differences remain unaffected by the Statement, which misleadingly notes that both sides have “offered convenience for family visits and lawyer’s meetings in accordance with their own rules.”

Yet, some still hope that the special position of Taiwanese people in Beijing's eyes might yield some groundbreaking improvements in China’s criminal justice system that might blaze a trail that could benefit others.

This article was published in the South China Morning Post on September 5, 2012 under the title “A Call from the Dark." It was published in Chinese in Taiwan's China Times on September 6, 2012.

Professor Jerome A. Cohen is professor and co-director of the US-Asia Law Institute at New York University School of Law and adjunct senior fellow for Asia at the Council on Foreign Relations. Yu-Jie Chen is a Taiwan lawyer and research fellow at the US-Asia Law Institute. See also www.usali.org